The invention relates to a shift device for a motor vehicle transmission.
German Published Patent Application No. 39 24 318 describes a shift device for a motor vehicle transmission, the shift device including a steering-column shift lever which is movable in two directions arranged orthogonally to one another, the steering-column shift lever being capable of being transferred along the first direction into at least one forward driving position (D) and one neutral position (N) and along the second direction into positions for successive (sequential) gear selection xe2x80x9c+xe2x80x9d xe2x80x9cxe2x88x92xe2x80x9d.
There are also various national and regional safety regulations.
Thus, the USA/Federal Government 49 CFR 571.102 applies. This specifies safety regulations for the transmission shift pattern, for the starter interlock and for the transmission braking effect. Furthermore, these regulations set forth the requirements for the transmission shift pattern in order to reduce the probability of shift errors. There is a following requirement for automatic transmissions with regard to the location of the transmission selector lever positions in passenger cars in S3.1.1:
There must be a neutral position between the forward driving positions and the reversing position. If a transmission shift lever fastened to the steering column is used, the movement from the neutral position into the forward position must take place clockwise. If the transmission shift pattern includes a parking position, this must lie at the end, next to the reversing position.
There is a following requirement for automatic transmissions with regard to the marking of the selector lever positions in S3.1.4:
In S3.1.4.1: Subject to the provision in S3.1.4.3, when the transmission shift pattern including a parking position, the marking of the selector lever positions, including the positions in relation to one another and to the selected position, must be indicated visibly to the driver, when one of the following conditions is fulfilled:
(a) The ignition is in the position in which the transmission can be shifted.
(b) The transmission is not in the parking position.
In S3.1.4.2: Subject to the regulation in S3.1.4.3, when the transmission shift pattern does not include a parking position, the marking of the selector lever positions, including the positions in relation to one another and to the selected position, must be indicated visibly to the driver at all times, when the ignition is in a position in which engine operation is possible.
In S3.1.4.3: Such information does not have to be indicated when the ignition is in the position which serves only for starting the vehicle.
Furthermore, safety regulation No. 114 xe2x80x9cTheft protectionxe2x80x9d in the USA/Federal Government 49 CFR 571.102 is to be adhered to.
S4.2.1 (a) Subject to the provisions in S4.2.2 (a) and (b), the key locking system, which, according to S4.2, is required in any vehicle having an automatic transmission with a parking position, must, in a test according to the procedure in S5.2, prevent the key from being withdrawn, unless the transmission or the transmission selector lever is locked in the parking position or is locked in the parking position as a direct result of the withdrawal of the key.
S5.2 Test procedure:
(a) The transmission selector lever is to be set to a position in which it will remain without assistance; this also includes a position between the engagement positions, with the exception of the parking position. An attempt is to be made, in every such transmission selection position, to remove the ignition key from every possible key position.
For Australia, the Australian Federal Government regulation No. 42/03 is to be adhered to with regard to the safety regulations.
Actuating devices are to be found there under point 8:
8.2 Standardized actuating devices for automatic transmissions
All motor vehicles, with the exception of vehicles of class L, which are equipped with an automatic transmission must fulfil the following requirements:
8.2.1 Selector lever position
8.2.1.1 Subject to the specifications in point
8.2.1.3 and in as much as the selector lever sequence includes a parking position, the marking of the selector lever positions, including the relation of the individual positions to one another and to the selected position, must lie within the driver""s field of vision, specifically whenever one of the following conditions applies:
8.2.1.1.1 The ignition is in a position in which the transmission can be shifted.
8.2.1.1.2 The transmission is not in the parking position.
8.2.1.2 Subject to the specifications in point
8.2.1.3 and in as much as the selector lever sequence does not include a parking position, the marking of the selector lever position, including the relation of the individual positions to one another and to the selected position, must lie within the driver""s field of vision, specifically whenever a driver is sitting on the driver""s designated sitting position.
8.2.1.3 Such indications need not appear when the ignition is in the position which is used solely for starting the vehicle.
8.2.2 Gear sequence
The sequence of the transmission selector lever positions must:
8.2.2.1 Include a neutral position which lies between the positions for reversing and forward driving; and,
8.2.2.2 When a parking position is provided, this parking position must lie at the end of the gear sequence, next to the reverse gear.
8.2.3 Transmission selector levers mounted on the xe2x80x9csteering columnxe2x80x9d (MA vehicles only):
The movement of the selector lever from the neutral position into reverse gear must take place clockwise; however, if all the selector lever positions lie on the right of the vertical longitudinal plane through the middle of the steering wheel, the movement of the selector lever from the neutral position into reverse gear must take place anti-clockwise. A device which indicates the selected transmission position must be provided. The movement of the indicator must, in general, lie in the same linear direction or direction of rotation as the movement of the transmission selector lever.
It is an object of the present invention to provide a cost-effective shift device.
The above and other beneficial objects of the present invention are achieved by providing a shift device as described herein.
One advantage of the shift device according to the present invention is that it may fulfil the conditions of various influential countries and may thus be sold, free of modification, in the various countries and therefore in large quantities.
A further advantage is that space is provided because there is no need for a shift lever on the center console. This space may be utilized for a holder for drink cans/bottles, which, particularly in the United States, is an advantage highly estimated by the customer and, due to the consequently increased vehicle sales, also leads to cost benefits.
As compared with shift devices without an indicator, in which a steering-column shift lever indicates the selected gear by the angular position of the steering-column shift lever, shift-lever locks, such as, for example, a lock which prevents the selection of the parking position at high speeds, may be dispensed with. Further cost benefits are achieved by mechanical locks being dispensed with in this manner.
Further refinements of the present invention which may be brought into agreement with statutory requirements and which are cost-effective. Thus, tipping actuation according to the present invention may be ergonomically beneficial and may be subject to lower mechanical load. At the same time, during tipping actuation it may not be necessary to grasp the steering-column shift lever during shifting, in contrast to abovementioned steering-column shift levers with indicating angular positions. Since slight tipping of the shift lever from one side, in a similar manner to the tipping of a conventional flasher lever, is sufficient for shifting the transmission, the vehicle driver applies only relatively low forces to the shift lever.
By providing an additional switching arrangement, the driver may have a choice of the operating elements in manual gear selection.
Another aspect of the present invention provides the driver a sporty sensation, in that his manual gear selection is executed positively within the engine rotational speed limits.
An upshift limitation which may be more comfortable than the abovementioned positive shift may be used. In the case of such an upshift limitation, the vehicle driver specifies the maximum gear capable of being selected by a shift program. That is to say, even in the manual mode, the transmission selects the optimum gear, but only up to the sequentially predetermined gear.
The foregoing features may be combined, in that a positive shift is assigned to switches arranged on the steering wheel for sequential shifting and a sequential upshift limitation is assigned to the steering-column shift lever. It may also be possible, as required, to assign a sequential upshift limitation to switches arranged on the steering wheel and positive shift to the steering-column shift lever.
The present invention is described in more detail below with reference to an example embodiment illustrated in the drawing.